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Jack Jack is offline
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Default 50 Dying batteries: Can they be shorted by cardboard if humid enough?

So I ran a little test.
Somewhat humid cardboard (sitting in my unheated garage in Seattle in the
middle of winter) measures over 100 megohms on my multimeter.
Sopping wet cardboard (tapwater) measures 1 megohm. Test points 3" apart
although it didn't seem to matter much.

Energizer rated at 2850 mah
Leakage into wet cardboard would be 1.5/1000= .0015 ma.
Time to discharge battery would be 2850/.0015=1.9 million hours or somewhat
over 200 years.

I suppose the water could have contained more ions than my tap water but
knowing that the human body is quite conductive I also checked the
resistance across my tongue and found it to be 1/10 that of the cardboard so
it would still take over 20 years to discharge the battery.
I guess I would look elsewhere for the dead battery gremlin.

"Thomas G. Marshall" . com
wrote in message news:PAsGh.235$1C6.156@trndny04...

I recently ordered on eBay 100 energizer AA batteries.

I tested them using a simple battery tester from radio shack. 4 were
dead,
one was near death, and 95 were at an identical high mark, but just a
"little" below an energizer I bought from a retail package from Home
Depot.
The tester is simple and unmetered, save for a "75%" mark. The needle
moves
up to *almost* the same spot as my control (retail) battery does.

They were shipped in 2 corrugated cardboard boxes, roughly the height of
an
AA cell. 50 in each, all standing up on the negative (flat) end. So
(especially if they are stacked) the top and bottom of all the batteries
are
touching the top and bottom of the cardboard box. HUGE speculation: If
the
cardboard is even minutely conductive (humidity, acidity, or whatever)
then
I have effectively a wired in parallel 1.5V "50xAA-amp" "battery" that is
shorting through its own packaging (?)

Is there another possibility for this, other than just lesser quality
batteries? And is the cardboard shorting even possible? I'm working with
the seller to try to figure this one out. He's asking about possibly
putting a plastic or foam sheet above or below them. I'd appreciate your
thoughts on all of this.